Stress can evoke a hypothalamic response, causing the release of hormones that in turn activate the hypothalamic-pituitary-adrenal (HPA) axis, which is involved in regulating emotions, metabolism, cognition, and the immune system. This in turn evokes a stress response which may disrupt blood sugar levels, suppress immune and inflammatory responses, interfere in memory formation, and disrupt feedback mechanisms intended to inhibit further stress responses. Chronic stress may result in impaired mental and physical health.
Existing medical treatments may have negative systemic side effects, while surgical treatments may be destructive and invasive. However, sound may be used to encode neural signals for therapeutic effect. Such auditory neuromodulation has been used to treat disorders in humans. For example, multiple studies have demonstrated that auditory neuromodulation may significantly decrease tinnitus. Tass, P. A., Adamchic, I., Freund, H. J., von Stackelberg, T., Hauptmann, C. (2012), “Counteracting tinnitus by acoustic coordinated reset neuromodulation.” Adamchic, I., Hauptmann, C., Tass, P. A. (2012), “Changes of oscillatory activity in pitch processing network and related tinnitus relief induced by acoustic CR neuromodulation.” Silchenko, A. N., Adamchic, I., Hauptmann, C., Tass. P. A. (2013), “Impact of acoustic coordinated reset neuromodulation on effective connectivity in a neural network of phantom sound.” This subjective decrease in tinnitus may be accompanied by modification of abnormal EEG rhythms. Adamchic, I., Toth, T., Hauptmann, C., Tass, P. A. (2013). “Reversing pathologically increased EEG power by acoustic coordinated reset neuromodulation.” In a rat model of antidepressant-like activity, treatment with auditory neuromodulation demonstrated effects similar to traditional chemical anti-depressants. Izvarina N. L., Lensman M. V., Murovets V. O., Savoxin A. A, “Antidepressant activity of Acoustical Neuro-Modulation in comparison with well-known antidepressants in forced swim test in rats” International Journal of Psychophysiology 69:3, September 2008, p. 288; Isvarina N. L., Lensman M. V., Murovets V. O., Savoxin A. A., “Investigation of antidepressants activity of sound beats created with different algorithms of modulation in comparison with antidepressants in forced swim test (FST) on rats.” Poster, 8th IBRO World Congress of Neuroscience/Florence-Italy Jul. 14-18, 2011. A493.
Standard methods of auditory neuromodulation may only achieve temporary results, as the patient may quickly accommodate to the auditory stimulation. Consequently, there exists a need for systems and methods for providing long-term treatment of physiological and psychological disorders using auditory neuromodulation. The envisioned embodiments satisfy this need by providing therapeutic nonlinear, multi-parametric modulation of sound. This therapeutic auditory stimulation may selectively influence the activation of the HPA axis, modulating the release of neurotransmitters to influence psychological and physiological behavior. Thus this therapeutic auditory stimulation may be used to treat anxiety disorders, autism spectrum disorders, and other psychological and physiological disorders described herein.